JP2002258025A - Method of correcting white defect in colored layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of correcting white defect in the color layer of a color filter by which a white defect occurring in the color layer can be corrected to give fine appearance without causing such problems that the white defect can not be completely corrected because of a small dropping amount of the coloring agent for correction, or on the contrary, that the coloring agent overflows from the white detect part because of a too large dropping amount of the coloring agent for correction. SOLUTION: The method of correcting white defect in the color layer in a color filter having at least the color layer on a transparent substrate includes the following processes. They are a removing process to irradiate the white defect part in the color layer with laser light through a mask of a specified pattern to remove the color layer including the white defect part in a specified pattern and a coating process to apply the coloring agent for correction on the removed part in the specified pattern in the removing process by using a coating needle having the top end which is smaller than the pattern of the removed part and is similar to that.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for correcting a white defect of a colored layer used for correcting a white defect when the colored layer of a color filter used in a liquid crystal display device or the like has a white defect. It is.

[0002]

2. Description of the Related Art In recent years, with the development of personal computers, especially portable personal computers, the demand for liquid crystal display devices, especially color liquid crystal display devices, has been increasing. In this color liquid crystal display device,
Usually, a color filter having three primary color patterns of red (R), green (G), and blue (B) is provided.
The liquid crystal operates as a shutter by turning on and off the electrodes corresponding to the R, G, and B pixels of the color filter, and light passes through the R, G, and B pixels to perform color display. Is performed.

In such a color filter, a color layer in which a pixel portion including R, G, and B is formed in a predetermined pattern on a transparent substrate is formed by photolithography, and a liquid crystal is formed on the color layer. Is formed on the transparent electrode.

However, when such a color filter is manufactured, for example, if foreign matter adheres to an exposure mask or a substrate or if exposure failure occurs due to other causes, the portion is not sufficiently exposed. Therefore, a colored layer is not sufficiently formed, and as a result, a so-called white defect may occur. Therefore, it is desirable not to mix such foreign substances during manufacturing or to prevent any exposure failure. However, as a practical problem, even when manufactured in an environment with a small amount of foreign substances such as a clean room, it is possible to completely remove foreign substances. It is impossible to manufacture a color filter without such conditions, and it is also impossible to create an environment in which exposure failure does not occur at all.

Therefore, it is necessary to correct the white defect generated in such a situation after forming the colored layer.

Conventionally, correction of white defects generated in a colored layer is performed by applying a colorant having the same color as that of the colored layer having the white defect to a portion of the white defect as it is. To fill the white defect.

As described above, when a white defect is corrected by simply applying a colorant of the same color as that of the colored layer while keeping the shape of the white defect generated in the colored layer as it is,
If the size or shape of the white defect part coincides with the shape of the tip of the coating needle used during coating, there is no particular problem, but the size of the white defect part is usually uneven. Therefore, the shape of the white defect portion and the tip of the coating needle often do not match. If the white defect does not match the shape of the tip of the coating needle, the following problem occurs.

If the white defect is larger than the tip of the coating needle, the amount of the colorant for correction applied by the coating needle is insufficient, and the entire white defect is corrected. The white defect part remains even after the correction.

If the tip of the application needle is larger than the white defect, the amount of the colorant for correction is too large, and the colorant for correction overflows from the white defect, resulting in overflow. The colored layer becomes thicker only in the portion.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and when the white defect generated in the color layer of the color filter is corrected, the amount of the colorant for correction is reduced. The white defect cannot be completely corrected because of the small amount, or the colorant does not overflow from the white defect because the application amount of the correction colorant is large. A main object of the present invention is to provide a method for correcting a white defect of a colored layer in a color filter.

[0011]

In order to achieve the above object, according to the present invention, there is provided a method for correcting a white defect of a colored layer in a color filter including at least a colored layer on a transparent substrate. By irradiating a laser beam passing through a mask of a predetermined shape to a white defect portion of the colored layer, a removing step of removing the colored layer including the white defect portion into a predetermined shape, and To the removed portion removed in a predetermined shape, using an application needle having a tip smaller than the shape of the removed portion and having a similar shape,
And a coating step of applying a correcting colorant.

As described above, in the method of the present invention, the colored layer including the white defect portion can be removed to a predetermined shape, that is, the shape of the mask of the laser beam by performing the removing step. In other words, at first glance, the white defect portion is broadened by the laser beam in this process, but this is a process performed to unify all the shapes and sizes of the white defect portions having different shapes one by one. This is a necessary step in the method of the present invention in order to cleanly correct a white defect portion in a subsequent coating step.

In the method of the present invention, after the removal step is performed, the coating step is performed, whereby the white defect portion can be corrected finely. This is because, in the method of the present invention, the removed portion is formed in a predetermined shape in the colored layer including the white defect portion in the removing step, so that the removed portion is smaller than the removed portion and has a similar shape (similar shape). This is because the colorant for correction can be applied using the coating needle provided at the tip, so that the colorant for correction can be applied to the removed portion without excess or deficiency.

According to the first aspect of the present invention, as described in the second aspect, both the shape of the portion removed in the removing step and the shape of the tip of the coating needle used in the coating step are different. The similarity ratio is preferably such that the length of one side of the tip of the application needle is 0.5 to 0.9, where 1 is the length of one side of the removed portion.

As described above, since the shape of the removed portion formed in the removing step and the shape of the tip of the coating needle are rectangular, the shape of the colored layer in the color filter is usually rectangular. , The corner portion (4
Even if there is a white defect in the (corner), it is preferable because it can be corrected.

In the present invention, when the length of one side of the removed portion is 1, the length of one side is 0.5 to 0.5.
It is characterized in that the colorant for correction is applied to the white defect using an application needle having a tip of 0.9. In the normal case, when the colorant is applied using an application needle having the same size tip as the removed portion, at the moment of application, even if the removed portion can be corrected cleanly, the correction colorant is not applied. Before drying, the applied colorant spreads to the surroundings, so that the colorant eventually overflows from the removed portion and cannot be corrected in many cases. In the present invention, at the moment when the correction colorant having a shape slightly smaller than the removed portion is applied, the removed portion is larger than the applied colorant and a white defect remains at the moment of application. However, since the colorant gradually spreads from the center to the outside, the white defect can be corrected cleanly.

Further, in the invention described in claim 1 or claim 2, as described in claim 3, a concave surface is formed at the tip of the coating needle so as to easily hold the colorant for correction. Preferably, it is formed.

This is because, by using the tip structure of the application needle in this manner, a coloring agent necessary for correcting a white defect can be reliably held.

Further, in the invention according to any one of the first to third aspects, as described in the fourth aspect, the viscosity of the modifying colorant is 50 to 180 cp.
It is preferably s.

As described above, in the present invention, the coloring layer including the white defect portion in the coloring layer is removed into a predetermined shape, and the correcting colorant is applied thereto using a coating needle, whereby the white defect portion is removed. How to fix. By making the viscosity of the correction colorant used here fall within the above range,
Since the applied colorant for correction gradually spreads around while maintaining the shape of the tip of the coating needle, it is possible to correct the color layer cleanly with less irregularities on the surface of the colored layer after the paint is cured. In addition, it is possible to provide a color filter having excellent smoothness without requiring any trouble in a polishing step or the like for subsequent correction.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION The method for correcting a white defect of a colored layer according to the present invention is a method for correcting a white defect generated in the colored layer in a color filter including at least a colored layer on a transparent substrate, the method comprising: A removing step of irradiating a white defect portion of the layer with a laser beam passing through a mask having a predetermined shape to remove the colored layer including the white defect portion into a predetermined shape; and a removal removed to a predetermined shape by the removing step. A coating step of applying a correction colorant to the portion using an application needle having a tip smaller in shape and similar to the shape of the removed portion. Hereinafter, each step in the method for correcting a white defect of a colored layer of the present invention will be described in detail.

FIG. 1 is a view showing the colored layer 2 of the color filter 1 before and after the removal step in the method of the present invention. FIG. 1A is a front view of the color filter before the removing step, and FIG. 1B is a front view of the color filter after the removing step.

First, the color filter 1 including at least the colored layer 2 on the transparent substrate 3 is applied with the method for correcting the white defect of the colored layer according to the present invention as described above.

The transparent substrate 3 used here is not particularly limited as long as it is usually used for a color filter. For example, a flexible substrate such as quartz glass, Pyrex (registered trademark) glass, or a synthetic quartz plate is used. Transparent rigid materials having no flexibility, or transparent flexible materials having flexibility such as transparent resin films and optical resin plates can be used.

The present invention is a method used for correcting a white defect 10 of a colored layer in a color filter formed on such a transparent substrate. This also includes the case of correcting a white defect generated in the colored layer before all the layers finally formed are formed. That is, for example, when only the colored layer and the black matrix layer are formed, the white defect in the colored layer may be corrected by the white defect correcting method of the present invention.
Therefore, in the color filter in this case, the layer formed on the transparent substrate at that stage, that is, in the above-described example, the coloring layer and the black matrix layer correspond to the color filter according to the invention.

Therefore, the color filter 1 according to the present invention is a layer containing at least a colored layer and formed on a transparent substrate when the white defect correcting method of the present invention is applied.

The white defect 10 to which the white defect correcting method of the present invention is applied is that a part of the colored layer is hardened due to poor exposure due to foreign matter adhesion to a mask or a substrate in a color filter colored layer manufacturing process. This is a defect that occurs when the color filter is not provided, that is, a defect in which the coloring layer is not formed in a portion where the coloring layer is supposed to be formed and the base material of the color filter is exposed.

It should be noted that the colored layer 2 in the present invention refers to a pixel portion of a plurality of colors, usually red (R), green (G), and blue (B).
And formed in various patterns, for example, a mosaic pattern, a triangle pattern, a stripe pattern, and the like.

In the present invention, such a white defect 10
Irradiating the colored layer including the white defect portion 10 with a laser beam through a mask having a predetermined shape to the colored layer 2 having Is characterized by performing

By thus irradiating the laser beam through the mask having a predetermined shape and removing the colored layer into the predetermined shape, the white defect portion 10, that is, the removal to be corrected, is performed in the subsequent coating process. The size and shape of the portion can be unified, and the removed portion (FIG. 1B)
Can be corrected neatly by using a predetermined application needle.

Therefore, in the method of the present invention, the shape of the laser beam (that is, the shape of the mask) applied to the white defect portion 10 of the colored layer 2 is determined by the shape of the tip of the coating needle used in the subsequent coating process. Have a mutual relationship with each other, and can be arbitrarily determined according to the tip shape of the application needle.

More specifically, the shape of the laser beam to be irradiated, that is, the shape of the mask is preferably rectangular, and particularly preferably substantially square. Since the colored layer in the color filter is usually rectangular, the shape of the laser beam is not affected even if there is a white defect at the corner (four corners in the case of rectangular) of the colored layer. This is because a rectangular shape can be removed cleanly. Also,
When the shape of the laser light is rectangular, the long side and the short side are present. Therefore, it is necessary to match the direction of the application needle of the same shape used in the application step (that is, the laser light The long side of the removed portion and the long side of the application needle need to be aligned, whereas a square is preferable because there is no need to align the direction of the application needle (see reference numeral 11 in FIG. 1B). ).

In the method for correcting a white defect in a colored layer according to the present invention, the white defect portion 1 generated in the colored layer by the above-described removing step is removed.
The colored layer is removed by irradiating the laser light to 0, and then a coating step of applying a correction colorant to the removed portion 11 is performed. In the application step of the present invention, an application needle is used to apply the correction colorant to the removed portion 11. Hereinafter, the coating needle used in the coating step of the present invention will be described in detail.

FIG. 2 is a schematic perspective view showing the tip of the coating needle 20 used in the coating step of the present invention.

The method of the present invention is characterized in that a coating needle having a tip which is smaller than the shape of the removed portion 11 formed by the laser beam irradiated in a predetermined shape in the above-mentioned removing step and has a similar shape is used. have.

As described above, the relationship between the removed portion 11 formed by the laser beam and the tip shape of the coating needle is smaller in the tip shape of the coating needle than in the removed portion, and both shapes are similar. Thereby, when correcting the removal portion by pressing the tip of the application needle to the removal portion,
The correction solution does not overflow from the removed part. Conversely, the coating after coating is incomplete and white defects do not remain, so that the finished product after correction can be cleaned.

The specific shape of the coating needle 20 used in the coating process of the present invention (irrespective of the size, merely the shape)
As described above, the shape of the removed portion formed in the white defect portion in the removing process performed before the coating process as described above may be the same as the shape of the laser beam mask. For example, when the removed portion is circular (when the laser beam mask is circular), the tip of the coating needle is also circular, and when the removed portion is rectangular (laser beam When the mask is square)
The shape of the tip of the coating needle may be rectangular. However, among various shapes, the shape of the removed portion is preferably substantially square for the above-mentioned reason, and therefore, the shape of the tip of the application needle is preferably substantially square in relation to this.

Further, regarding the size of the removed portion and the size of the tip of the application needle in the method of the present invention, it is necessary that the size of the tip of the application needle is smaller than the size of the removed portion. If the tip of the applicator needle is larger than the removed part,
This is because when the colorant for correction is applied using the coating needle, the paint overflows from the removed portion and cannot be corrected cleanly.

In the present invention, the similarity ratio (ie, the size of the removed portion and the tip of the application needle) when the shape of the tip of the removed portion 11 and the tip of the coating needle 20 is substantially square is determined in the present invention. When the length of one side is 1, the length of one side of the tip of the application needle is preferably 0.5 to 0.9.

As described above, the tip of the application needle is preferably smaller than the removed portion. However, when the length of one side of the removed portion is 1, the length of one side of the tip of the application needle is smaller than 0.5. This is because, in some cases, the size of the tip of the application needle is too small compared to the removed portion, and as a result, it may not be possible to completely correct the entire removed portion. On the other hand, if the length of one side is larger than 0.9, it cannot occur that the removed portion cannot be completely corrected, but the colorant for correction after being applied immediately dries. Since it is not a thing, it is conceivable that it gradually spreads to the periphery (outside) of the removed portion. In such a case, if the similarity ratio between the removed portion and the tip of the application needle is greater than 0.9, the applied correction colorant overflows from the removed portion before drying, and as a result, the removed portion is removed. This is because it is possible that the correction cannot be made cleanly. Further, that the similarity ratio is larger than 0.9 means that the size of the removed portion and the tip of the application needle are almost the same, and in this case, when the application step is performed by lowering the tip of the application needle to the removed portion. A considerable degree of accuracy is required, which is not preferable because yield is expected to decrease.

In the coating step of the present invention, specifically, it is preferable to use a coating needle shown in FIG.

The tip 21 of the application needle 20 shown in FIG. 2 has a substantially square shape, and the length of one side is about 50.
μm. Therefore, when the correction colorant is applied using the application needle 20, the length of one side of the removed portion is about 55 to 100 μm based on the similarity ratio described above.

It is preferable that a concave portion 23 is formed on the application surface 22 at the tip 21 of the application needle 20 as shown in the figure. In the coating step of the present invention, a correction colorant is applied to the tip of the coating needle as shown in the figure, and the coating needle with the colorant is pressed against the portion removed in the removal step, that is, the white defect portion ( The correction colorant is applied by performing an image such as stamping.
Therefore, by forming the concave surface 23 as shown in the figure, the correction ink can be easily held on the application surface 22.

Further, as shown in FIG.
It is preferable that the shape is such that the depression is deeper toward the center. This is because when the colorant is applied by pressing the application needle, the colorant tends to be applied more to the edge part than to the center part of the application needle, so that the colorant tends to be thinner at the center. This is because a large amount of the coloring agent is added in advance to the coloring agent so that the coloring agent is uniformly applied.

Further, the coating needle 20 used in the method of the present invention
In this case, it is preferable that the tip portion is tapered as shown in FIG. 2 (see reference numeral 24). This is because, when the same application needle is used continuously, the correction colorant comes up above the application needle, so that it may be difficult to apply the correction colorant quantitatively. Therefore, by making the tip of the application needle tapered, it is possible to prevent the correction colorant from rising above the application needle, thereby enabling quantitative application.

Next, the correcting colorant used in the method of the present invention will be described.

The method of the present invention is a method for correcting a white defect portion generated in a colored layer of a color filter. Therefore, any colorant that can be used as a color layer can be used as the colorant for correction used in this correction. Further, in the normal case, since the coloring layer has three colors of red (R), green (G) and blue (B), it is necessary to use a correcting colorant of the same color as the color of the coloring layer having a white defect. It is.

However, as the colorant for correction in the present invention, a colorant having a viscosity of 50 to 180 cps is preferable, and a colorant having a viscosity of 80 to 150 cps is more preferable. The reason why a certain degree of viscosity is required is that, in the present invention, the shapes of the removed portion and the tip of the application needle are previously made similar to each other, so that the colorant for correction maintains the shape when applied by the application needle. It is preferable to spread to the surroundings (outside) in the state described above, and this requires a viscosity in the above range.

More specifically, the viscosity of the modifying colorant is 5
If it is lower than 0 cps, the coloring agent may not adhere well to the tip of the application needle, and as a result, the coloring agent may not be applied to the portion to be corrected, that is, the removed portion. Further, if the viscosity of the colorant for correction is higher than 180 cps, the colorant is not likely to be attached to the center of the tip of the coating needle, and as a result, the corrected portion may look like a white defect.

The color filter in which the white defect of the coloring layer has been corrected in this way can reproduce the color faithfully in all the pixels, and is of very high quality.

The present invention is not limited to the above embodiment. The above embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and has the same effect. Within the technical scope of

[0052]

The present invention will be further described with reference to the following examples.

For the correction colorant used in the method of the present invention, each color of red, green, blue and black is prepared, and for each color, several types of correction colorants having different viscosities are adjusted. White defect correction method was performed.

For the color layer to be corrected, the same color as that of the colorant for correction is prepared, and the removal step of the present invention is performed in advance for each color layer to form a square removal portion having a side of about 70 μm. did.

The coating needle used had the same shape as the coating needle described with reference to FIG. In other words, the shape of the tip is a substantially square shape, the length of one side is a coating needle of about 50 μm, a concave surface is formed on the coating surface of the tip, and the tip is tapered. Is what it is.

The composition common to the correction colorants of each color is as follows. Resin: acrylic resin Monomer: DPHA (dipentaerythritol hexaacrylate) Initiator: α-aminoketone diluent Solvent: propylene glycol monomethyl ether acetate

The following Tables 1 to 4 show the results of the white defect correcting method of the present invention when using various correcting colorants having various viscosities for each color.

[0058]

[Table 1]

[0059]

[Table 2]

[0060]

[Table 3]

[0061]

[Table 4]

As is clear from Tables 1 to 4, when the viscosity of the correction colorant is 50 to 180 cps (in the case of the embodiment), it becomes difficult to supply the correction colorant or the correction colorant is corrected. In some cases, the uncoated portion remains extremely small at the center of the portion to be removed, but it can be seen that the correction can be made generally well. On the other hand, when the viscosity of the colorant for correction is lower than 50 cps or higher than 180 cps, it becomes difficult to supply the colorant for correction, or a large uncoated portion is required in the center of the white defect portion to be corrected. May remain, and a good correction could not be made.

This example also shows that the viscosity of the modifying colorant used in the method of the present invention is preferably 50 to 180 cps.

[0064]

According to the present invention, it is possible to remove a colored layer including a white defect portion into a predetermined shape by first performing a removing step. Further, the colored layer including the white defect portion is smaller than the predetermined shape and similar in shape to the predetermined shape. By applying the colorant for correction using the application needle described in the above, the colorant for correction can be applied to the removed portion without excess and deficiency, and the white defect can be corrected much more clearly than in the past.

[Brief description of the drawings]

FIG. 1A is a front view of a color filter before a removing step, and FIG. 1B is a front view of the color filter after a removing step.

FIG. 2 is a schematic perspective view showing a tip portion of a coating needle used in a coating step of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Color filter 2 ... Coloring layer 3 ... Transparent substrate 10 ... White defect 11 ... Removal part 20 ... Coating needle 21 ... Tip of coating needle 22 ... Coating surface 23 ... Concave surface 24 ... Taper

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuki Nakanishi 1-1-1, Ichigaya-Kaga-cho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Mitsuru Kusakabe 1-chome, Ichigaya-ka-cho, Shinjuku-ku, Tokyo No. 1-1 Dai Nippon Printing Co., Ltd. F-term (reference) 2H048 BA02 BA11 BA45 BB02 BB42

Claims (4)

[The claims] 1. A method for correcting a white defect in a colored layer of a color filter including at least a colored layer on a transparent substrate, wherein the white defect portion of the colored layer is irradiated with a laser beam through a mask having a predetermined shape. According to, a removing step of removing the colored layer including the white defect portion into a predetermined shape, and a removed portion removed into a predetermined shape by the removing step,
A coating step of applying a colorant for correction using a coating needle having a tip smaller in shape and similar to the shape of the removed portion, and a method for correcting white defects in the colored layer. 2. The shape of the removed portion removed in the removing step and the shape of the tip of the coating needle used in the coating step are both rectangular, and the similarity ratio is the length of one side of the removed portion. 2. The method according to claim 1, wherein the length of one side of the tip of the coating needle is 0.5 to 0.9, where is 1. 3. The colored layer according to claim 1, wherein a concave surface is formed at a tip of the coating needle so as to easily hold a colorant for correction. Defect correction method. 4. The correction colorant has a viscosity of 50 to 180.
The method according to any one of claims 1 to 3, wherein the method is cps.